{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:39:49Z","timestamp":1760240389686,"version":"build-2065373602"},"reference-count":12,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,5,27]],"date-time":"2019-05-27T00:00:00Z","timestamp":1558915200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002803","name":"Fondazione Cariplo","doi-asserted-by":"publisher","award":["EMPATIA@Lecco project, Rif. 2016-1428"],"award-info":[{"award-number":["EMPATIA@Lecco project, Rif. 2016-1428"]}],"id":[{"id":"10.13039\/501100002803","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100009882","name":"Regione Lombardia","doi-asserted-by":"publisher","award":["n. 18092\/RCC del 05\/08\/2013"],"award-info":[{"award-number":["n. 18092\/RCC del 05\/08\/2013"]}],"id":[{"id":"10.13039\/501100009882","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>Variable-Stiffness Actuators are continuously increasing in importance due to their characteristics that can be beneficial in various applications. It is undisputed that several one-degree-of-freedom (DoF) solutions have been developed thus far. The aim of this work is to introduce an original two-DoF planar variable-stiffness mechanism, characterized by an orthogonal arrangement of the actuation units to favor the isotropy. This device combines the concepts forming the basis of a one-DoF agonist-antagonist variable-stiffness mechanism and the rigid planar parallel and orthogonal kinematic one. In this paper, the kinematics and the operation principles are set out in detail, together with the analysis of the mechanism stiffness.<\/jats:p>","DOI":"10.3390\/robotics8020039","type":"journal-article","created":{"date-parts":[[2019,5,27]],"date-time":"2019-05-27T11:19:27Z","timestamp":1558955967000},"page":"39","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["On a Two-DoF Parallel and Orthogonal Variable-Stiffness Actuator: An Innovative Kinematic Architecture"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4961-376X","authenticated-orcid":false,"given":"Matteo","family":"Malosio","sequence":"first","affiliation":[{"name":"Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato, Consiglio Nazionale delle Ricerche, via Alfonso Corti 12, 20133 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"Corbetta","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, Via la Masa 1, 20156 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francisco","family":"Ram\u00ecrez Reyes","sequence":"additional","affiliation":[{"name":"Dipartimento di Meccanica, Politecnico di Milano, Via la Masa 1, 20156 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8840-8497","authenticated-orcid":false,"given":"Hermes","family":"Giberti","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria Industriale e dell\u2019Informazione, Universit\u00e0 di Pavia, Via ferrata 5, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2700-5093","authenticated-orcid":false,"given":"Giovanni","family":"Legnani","sequence":"additional","affiliation":[{"name":"Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato, Consiglio Nazionale delle Ricerche, via Alfonso Corti 12, 20133 Milano, Italy"},{"name":"Dipartimento di Ingegneria Meccanica e Industriale, Universit\u00e0 di Brescia, Piazza del Mercato 15, 25121 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8541-3546","authenticated-orcid":false,"given":"Lorenzo","family":"Molinari Tosatti","sequence":"additional","affiliation":[{"name":"Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato, Consiglio Nazionale delle Ricerche, via Alfonso Corti 12, 20133 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1601","DOI":"10.1016\/j.robot.2013.06.009","article-title":"Variable Impedance Actuators: A Review","volume":"61","author":"Vanderborght","year":"2013","journal-title":"Robot. 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